@inbook{blum2007feedback, booktitle = {New Technology Frontiers in Minimally Invasive Therapies}, title = {Advanced Augmented Reality Feedback for Teaching 3D Tool Manipulation}, publisher = {Lupiensis Biomedical Publications}, address = {Leece, Italy}, pages = {223--236}, chapter = {25}, author={Tobias Blum and Tobias Sielhorst and Nassir Navab}, year = 2007 }